Pets and pregnancy – A warning

August 3, 2008

A new study shows that pregnant women who use flea and tick shampoos on pets may double the risk of autism in their children. This preliminary finding comes from the Childhood Autism Risks from Genetics and the Environment study (CHARGE) – a case-control study from the University of California Davis, in the US.

The results are part of an ongoing research project which is following 2,000 children – some with autism, some with developmental delay, and some with typical development – and compares individual genetic patterns with exposure to medications, chemicals, food products, and other environmental factors.

It is believed that it is pyrethrins, commonly used chemicals in insecticides, that may play a role in triggering autism in certain children. Pyrethrins are extracted from Chrysanthemum flowers and are regarded as low in toxicity and there are commercial pyrethrum formulas that are considered safe to use in food preparation areas where flies and other insects can be found. One other product where Pyrethrins are widely used is in lice-control shampoos for humans and pets.

As I mentioned earlier, this is only a preliminary study but it would be a sensible precaution for pregnant women to avoid contact with lice-control shampoos. Let someone else shampoo the dog, or look for shampoos that treat lice naturally with ingredients such as tea tree oil, and not pyrethrins.